The Department of Law, in a statement, says the attorney general’s office has a duty "to uphold and defend the Alaska Constitution, which it intends to do." The department says the state’s position will be more fully laid out in future court filings.

Alaska voters, in 1998, approved a constitutional amendment defining marriage as between one man and one woman.

Five same-sex couples - four married outside Alaska and one unmarried couple - sued in federal court last month, seeking to strike down the ban on gay marriage. They say the ban violates their right to due process and equal protection under the U.S. Constitution.